The on-field portion of the 2014 NFL Scouting Combine got underway Saturday morning in Indianapolis with workouts by the offensive linemen and tight ends.

The overall athleticism of offensive linemen has seemingly increased each year, and the 2014 class continued that trend with its impressive showing today.

The tight ends were underwhelming as a whole, with a mix of positive and negative notes to surround each player as none of them were able to put together a complete day.

Following my observations, you can also find a few additional notes from BBD editor Dan Hope, along with a link to full combine results.

Top Offensive Tackles Cement Their Draft Stock

Far and away, the most impressive prospects on the field Saturday were the top three offensive tackles in this year’s draft class: Jake Matthews, Greg Robinson and Taylor Lewan. While 40-yard dash times are not as important for offensive linemen as they are for most positions, it’s still worth noting that Lewan posted the best time of any offensive lineman with an official 4.87-second 40-yard dash.

The second-fastest 40-yard dash among offensive linemen came from Robinson, who delivered an impressive time of 4.92 seconds at 6’5″ and 332 pounds. He also pumped out 32 reps of 225 pounds in the bench press Friday, while he checking in with 35” arms.

Jake Matthews had the least impressive numbers of the trio but was still outstanding, clocking an official forty yard dash of 5.07 seconds and putting up 24 reps on the bench press while checking in at 6’5 1/2″ and 308 pounds with 33 3/8″ arms.

All three players displayed excellent fluidity, bend, foot speed and change-of-direction skills while completing the on-field drills. I expect all three players to be selected among the top-15 selections of the 2014 NFL draft.

Second-Tier Offensive Tackles Impress

Miami offensive tackle Seantrel Henderson has his share of questions to answer for NFL teams, but the on-field portion of his Scouting Combine performance left little doubt he can succeed in the NFL. After measuring in at 6’7” and 331 pounds, Henderson impressed with a 5.14-second 40-yard dash. He has an impressive, muscular build and is the type of player you would want to send off the bus first. His foot speed and change-of-direction skills are excitable.

Nevada’s Joel Bitonio was also among the standouts from the offensive line group. Bitonio had one of the day’s most complete workouts turning in a 4.97 40-yard dash, 9’6” broad jump, 7.37 3-cone drill and a 4.44 short shuttle. While some suggest his best fit is at guard, he has displayed top-end athletic ability and should be given the opportunity to succeed at tackle first. Bitonio had an excellent showing against Anthony Barr, one of the draft’s top pass-rushing prospects, when Nevada played UCLA in 2013.

Standout Guards

LSU guard Trai Turner is a player that jumped off the film for me, and he stood out in the 40-yard dash Saturday with a 4.93-second time. Unfortunately for Turner, he suffered an injury on his second run of the 40 and was unable to continue in on-field drills.

Xavier Su’a-Filo from UCLA excelled on the field Saturday with fluid movements and excellent foot speed. He has collegiate experience at both guard and tackle. Combining versatility with an excellent collegiate career and a good combine performance, Su’a-Filo looks like a potential end of the first round pick.

Mississippi State guard Gabe Jackson didn’t post the best times, finishing with a 5.51-second 40, he looked great doing it. For a man of his size at 6’3” and 336 pounds, Jackson moves well and it is not a laborious effort. He operates well in a phone booth and is a Day 1 starter at guard.

Not The Greatest of Days

Alabama offensive tackle Cyrus Kouandjio left the field with several questions to answer. After struggling mightily against Virginia Tech and Oklahoma this season, it appears Kouandjio has a long way to go in his development. Coupling his poor 40-yard dash time of 5.59 seconds with stiff movements and tight hips throughout today’s drills, it is looking more like he will need to kick inside to guard in the NFL. Making matters worse, Kouandjio has reportedly been failed by several teams on his physical, according to NFL Network’s Ian Rapoport, due to an arthritic knee.

My top guard entering the day was Stanford’s David Yankey, but I had questions about his heavy feet and those were not answered today. Yankey has solid functional strength but failed to display fluidity or solid change-of-direction skills Saturday. Yankey is a better football player than athlete, but he was disappointing at the combine.

Mixed Bag for Tight Ends

Despite a day cut short by injury, Eric Ebron still impressed at the NFL Scouting Combine. (Photo: Brian Spurlock — USA Today Sports)

Despite only being able to run the 40, Eric Ebron might have had the best day of any tight end. He turned in an official time of 4.60 seconds, but a hamstring injury kept him from participating in the rest of the drills. Ebron confirmed his speed and has a chance of being the first top-10 tight end selection since 2006.

Jace Amaro ran an impressive 4.74-second 40 yard dash and turned in 28 reps on the bench press, but that is where the positives end. He dropped and bobbled several passes while failing to run crisp routes in drills.

USC’s Xavier Grimble did not participate in the 40 yard dash but began to answer questions about his receiving ability. Underused on a limited route tree in college, Grimble displayed solid breaks and burst at the top of his routes while locating the ball well and catching it with soft hands.

Another non-40-yard dash participant, Notre Dame’s Troy Niklas, failed to answer questions about his raw receiving ability. While there is no 40 time to validate his speed, Niklas appeared slow as a route runner. He had multiple drops in the gauntlet drill and looked even worse running routes and catching passes.

Dan Hope’s Picks:

- Cameron Fleming, RT, Stanford – Yankey wasn’t the only Stanford offensive lineman to disappoint Saturday. Fleming struggled throughout his workout, looking sloppy throughout the positional movement drills while ranking among the worst times in the 3-cone drill (8.24 seconds) and 20-yard shuttle (5.00 seconds).

- Jonotthan Harrison, C, Florida – Harrison had one of the better days among offensive linemen. He showed quick feet and good change-of-direction skills with natural knee bend in the positional drills, while he put up solid marks in the 40-yard dash (5.15 seconds) and broad jump (9’5″).

- Matt Patchan, OT, Boston College – Patchan had an outstanding day in the explosion drills, running a 4.97-second 40 while leading all offensive linemen with a 32″ vertical jump. But will it translate to the field? Patchan is an intriguing sleeper prospect, but he was sloppy in positional drills and his age and injury history will keep many teams away.

- A.C. Leonard, TE, Tennessee State - Off-field troubles led Leonard out of Florida and to Tennessee State, and the early entrant might still be a draft longshot, but he made a strong case himself Saturday. He ran the fastest 40-yard dash among tight ends (4.50) and was impressive catching the ball downfield in drills.